Graphical Abstract
![](https://wqketang.oss-cn-beijing.aliyuncs.com/zip-unzip/zip-1084b3bd-ed0f-42cd-baa4-dee1e8f66062/nr-8-10-3205/files/nr-8-10-3205-FE1.jpg?Expires=1739870171&OSSAccessKeyId=STS.NT28qGGsyFYd3ME3qtkU9D2ZS&Signature=xyib4xYumtIM7lXhJl40i8NYrm0%3D&security-token=CAISywJ1q6Ft5B2yfSjIr5eHc8vzqqxY8ZuPMWv013EhZ9oVq%2FfxsTz2IHtKenhsBOsbtfk1mG5W5%2FgZlqJ9SptIAEfJa9d99MzBVvgc2tCT1fau5Jko1beHewHKeTOZsebWZ%2BLmNqC%2FHt6md1HDkAJq3LL%2Bbk%2FMdle5MJqP%2B%2FUFB5ZtKWveVzddA8pMLQZPsdITMWCrVcygKRn3mGHdfiEK00he8TouufTinpHMskGA1Aell7Mvyt6vcsT%2BXa5FJ4xiVtq55utye5fa3TRYgxowr%2Fwo0v0YpGya5YzHXwcPskvdKZbo78UqLQlla6w%2BGqFJqvPxr%2Fp8t%2Fx5fWJKAezhVgs8cVM8JOjIqKOscIsipkmoxV8YFV55c8Fdm%2BgUooJVgIMhTnduUfAPJAGOxzJitP%2BUVGGphr60TEnBL4rB5MUctfzRp5axMwTUTzDnGoABmf5JZxNQ%2Fp6hVt7Xbd%2FKctsP8KiJsJguGmWXG6ubZj2u3KMbL6fDomDDJ6%2B%2BzGSQ041gcjiT4OMo94H1sHIzrijufa2PjfEJ1zB%2FdAqLgHor398Tv8JY5qGw4jANoNpGRKGUSVMaWNx2WGC8i2e%2FcHOKoVPmi1x2z1feyofpRfcgAA%3D%3D)
A Cu nanowire (NW)/cuprous oxide (Cu2O)-based semiconductor-liquid junction solar cell with a greatly enhanced efficiency and reduced cost was assembled. The Cu NWs function as a transparent electrode as well as part of the Cu NWs/Cu2O coaxial structures, which remarkably benefit the charge separation. The best solar cell reached a conversion efficiency as high as 1.92% under a simulated AM1.5G illumination, which is 106 times higher than that of cells based on fluorine-doped tin oxide and Cu2O.
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